[net.micro.cbm] 1541 Head Alignment

aak@CS-Mordred (Alejandro Kapauan) (03/02/84)

Does anyone out there know what can be done to prevent the 1541
drive from drifting out of alignment? I have the old drive which is
lighter in color than the new one. For about a month after aligning
it, it works perfectly. Then a month or so later, it begins to
develop the familiar signs of head misalignment. Then I have
to perform the alignment again.

To align the head, I remove the chassis from the plastic case,
turn it on its side, then slightly loosen the two stepper motor
hold-down screws accessible through cutouts in the chassis.
I hookup the drive to the computer, insert a known good disk
(I don't have an alignment disk, so I use the 1541 demo disk),
then run the program below to step the head from track to track.
I then turn the stepper motor slightly (its mounting holes are
oval, so it can turn a bit) until there are no signs of read
errors (steady on drive light, no blinking or flickering) through
the outermost to innermost tracks. I then tighten the screws.
You might try this if you are desperate. My last alignment lasted
longer than normal, since Christmas.

10 CLOSE15:CLOSE2:OPEN15,8,15
20 OPEN2,8,2,"#"
30 FORS=0TO10:FORT=1TO35
40 PRINT#15,"U1:";2;0;T;S
50 PRINT"TRACK"T"  SECTOR   "S
60 NEXTT:NEXTS
70 CLOSE2:CLOSE15

Does the new drive still have head alignment problems? Would
Commodore be willing to sell just the drive mechanism?
Please post responses to the net.

Thanks in advance.
-AQ Kapauan
....!pur-ee!purdue!aak
(aak@purdue   CSNET/ARPA)